Desulfurizing method for treating refractory ores.



E. H. DICKIE.

DESULFURIZING METHOD FOR TREATING REFRACTORY ORES APPLICATION FILED IAN.25, I9I5.

1,177,396. y Panama Mar. 28,1916.

2 SHEETS-SHEET l.

"wfg- E. H. DIKI.

DESULFURIZING METHOD FOR TREATING REFRACTORY ORES.

APPLICATION FILED IAN.25, |915.'

Patentd Mar. 28, 1916.

2 SHEETS-SHEET 2.

:.Ewi

EDWARD HALE DICKIE, OF GOLDROAD, ARIZONA.

Specification of Letters Patent.

DESULFURIZING- 'METHOD FOR TRE'ATING- REFRACTORY ORES.

Application led January 25, 1915. Serial No. 4,233.

T all whom it may concern Be it known that I, EDWARD H. Dioxin, a citizen of the United States, residing at Groldroad, in the countyl of Mohave and State of Arizona, have invented certain new and useful Improvements in Desulfurizing Methods-for Treating Refractory Ores; and I do declare the following to be a full, clear, and exact description of the invention, such which it appertains to make and use the same. t

My invention relates to improvements in methods for accomplishing preliminary treatments of gold, silver, platinum and other ores wherein sulfur isfound in combination with any of the above metals, or in combination with any of the base metals. Actual experience has taught that little or no recovery of gold, silver, or platinum values is made by cyanidation or kindredl processes, unless such ores are given a preliminary treatment such as roasting or a desulfurizing treatment. The roasting process has proved ineifective in many ways and it is to provide a new and novel method for removing the sulfur from the ores that I have primarily provided the invention to be hereinafter more -clearly described and explained.

J, -to the accompanying drawings, in which:

i Figure 1 designates a vertical section of a preliminary treatment tank equipped with Fig. 2 is a top plan view of the tank; Fig. 3

is a vertical section through one of the pneu .50 spigot 3 being provided for removing liquids y which have been drained through said filter. The tank may further be equipped with an appropriateJ form of door lat its lower end. 0

Standing upright within the tank 1 1s a plurality of pneumatic agitators 5, these as will enable others skilled in the art to A In describing my invention I shall' refer mechanism for carrying out the process;v

agitators being here shown. in the form of upright tubes (see more particularly Fig. 3)y having linings 6 of aluminum and coverings 7 of such material. Each of the agitators 5 is further equipped with a nozzle 8 located within its lower end and carried by an air tube 9 through which compressed air is forced, all of these nozzles being so designed as to force any solution within the agitators outwardly against the lining 6 as will be evldent by inspection of the illustration.

The agitators 5 may be carried and operated by any appropriate means, this means being here shown in the form of a tripod 1,0 from which, the agitators are suspended by hangers 11, the arms of the tripod being provided with rollers12 which run upon a track 13 at the top of the tank 1. For rotating the tripod 10, the means indicated at k14: in Figs. 1 and 2 may be employed, or any Vother suitable driving mechanism may be provided, it being only necessary that the numerous agitators 5 be moved through a solution deposited in the'tank..

As most clearly seen in Fig. `1, the pipes 9 for furnishing compressed. air to the nozzles 6 are in valved communication with a trio of other pipes 9 radiating from a central `air supply coupling 9 located at the center ofl the tripod, 1,0, compressed air being fed to this coupling by a supply pipe 9a.

The apparatus thus described or an analogous disposition of parts may be employed,

but since no unnecessary parts of the device are located within the tank, the Structure illustrated in the drawings is preferable.

In. effecting the process, the ores to be treated are first ground toa mesh ranging from a 150 to a 200 grade and such ground ore is mixed with a caustic soda solution,- this mixing being either done in the tank 1 or at vsome remote point. The liquid mixture, at any rate, is Iat one time or anotherdeposited in the tank 1 and by the mechalnism 14, or its equivalent,the tripod 10 is rotated to cause the pneumatic agitators 5 to move through the solution. At the same time, compressed air is admitted through Patented Mar. 2s, 1916.

the pipe 9a to be discharged upwardly from the nozzles 8, thus creating a suction within the agitators and causing the solution to move upwardly therein, thus causing such solution to forcibly contact with the aluminum lining 6 which chemically acts there-v onin a manner to be more clearly explained,

aluminum coverings A7 thereof are being forced against and through the' solution .in the` tan thus also chemically acting thereon.

It is to be noted that by the structure above described, the solution Within the tankv is simultaneously aerated, agitated,

'and subjected to metallic aluminum, these simultaneously occurring actions tending to eectively accomplish the desulfurization of V i the ore being treated. -This process, I shall endeavor to cover as fully as possible both in description andvby equation inthe followmg- I Y l A It is to be remembered. first, that ores of gold and silver that carry dierent metal and mineral contents in combination with sulfur, must necessarily receive a treatment suitable to the ore contents-for its proper reduction. As all example: An ore that contained `lead sulfate would be refractory be cause the gold and silver lWould be"coated with the sulfate ofA lead. In this case, an addition of an alkaline earth or metal acetates would` bev added to the preliminary treatment solution.' Thus, sodium acetate will dissolvel lead sulfate, the lead Will re-v act with the sulds/ and form lead sulld.;

Again the caustic soda reacts with the leadl sulfates which are changed to lead hydroxid, the readjustment causing the coating to become permeable. compounds are changed to the hydroxids. Organic matter is removed or oxidized more readily by aeration of thefsolution. Where so,-

dium hydroxid is present.4 vThe oxidation of the ferrous compounds is rapid in a caustic soda solution in the presence of oxygen, obtained by the aeration given the solution in the apparatus (z'. e., the pneumatic agitators).

Potassium acetatesv dissolve metallic sul fates and becausel ,of the anity for those sulfates, tend to hasten' the change of sulv,Iids tol sulfates in the presence of oxygen.

- It will hasten any action which, IWill bring about the solution of any metallic substance with which `it will unite. .Therefore, practice, I use a caustic soda solution,

Similarly, many other i NaOH.4 ertai'n sulfid` ores are desulfuri iz"edby this solution in the presence of me-v tallic aluminum producing sodium sulfd which remains in solution andvis drained from the ore. Orcs containing the sulfates and sullids of lead, zinc, antimony, arsenic, etc., are desulfurized byy a caustic soda soluf tion in the presence of metallic valuminum c and zinc allo or'by `the addition of an. acetate of an al ali earth ormetal to' the solution. The' desulfurizing is caused bythe action ofthe chemical on the sulfates and sulidsaswell as the formation of hydrogen 'gas by the action of caustic soda on metallic aluminum in .the presence ofthe sulfates.

and sulds f the metal contents of the ore.

Again hydrogen gas is evolved `vvheregzinc I acetate is used in the'solutions the action 7 ofthe latent acid contents of the ore upon the zinc setting the gas free. The action of hydrogen gas in combination With the reducing action of the acetate earths or metals desulfurizes the refractory ores and prepares such ores for the-actual treatment by ,c

.-cyaniding or other kindred processes, after first draining the solution from the ores. l

The reduction of sulfurmetal contents of i( an, ore is presumably. as follows when treated by NaOH and 2Al: ,c '2A1+2Naon+2n 2o:Nanna-pen; From the foregoing description, when considered in connection with the accompanyingillustration, it Willbe seenthata v comparatively simple process-has been provided for accomplishing the yobject of the invention, yet that such process will be highly efficient in operation and-Will readily f decompose anyV prevalent-'sulfur or sulfur` compounds in most forms of refractory ores.

I claim The 'method' of treating refractory ores.

consisting in mixingtheinely ground ore with a solution of caustic soda `and potassiumacetate, agitating the mixture-'1n the.- presence of a metallic value precipitant, and' finally removing the solution. f

In testimony whcrof I lhave hereunto set my hand in presence of two subscribing wit- EDWARD HALE DICKIFL Witnessesz, i

f G.' A. SfroNnY, A B. TAYmR.. 

